JPS5848773A - Fuel supplying device for fuel injecting engine - Google Patents

Abstract

PURPOSE:To promote the atomization of fuel and contrive the improvement of fuel consumption and the reduction of noxious constituents in exhaust gas by a method wherein an air injecting port is provided so as to make air collide against the injecting fuel, while a heater is attached to a suction air wall, against which the injecting fuel is colliding, and an ignition timing is adjusted so as to be immediately before or after the closing of a suction valve. CONSTITUTION:The fuel injection is effected in each fuel injecting valves 13 at the initiating period of a compression stroke or the period wherein the suction valve 25 is just closed or immediately after the same is closed. In case of the fuel injection, suction air stream flowing toward the combustion chamber 21 is not existing, therefore, the injected fuel is collided against the heater 18 correctly without being deviated. The injected fuel from the fuel injection valve 13 is collided against the injected air from the air injecting port 15 and thereby promoting the atomization of the fuel. Upon the cooling of the engine, or a cooling water temperature is lower than a predetermined value, a switch 38 is closed to supply a current to the heater 18 and thereby operating the heater 18. A thermostat 40 controls the current for the heater 18 and the abnormal temperature rise of the heater 18 may be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel supply system for a fuel injection engine that can improve atomization and evaporation of fuel injected from a fuel injection valve.

In a fuel injection engine', fuel is injected from each fuel injection valve toward the intake boat, and the fuel collides directly with the intake port wall without being sufficiently atomized, causing fuel to adhere to the wall and stagnate. Compared to carburetor-type engines, the contact time between the fuel and intake air is shorter, resulting in poor atomization of the fuel, resulting in poor fuel consumption efficiency and an increase in the amount of unburned components in the exhaust gas. . Furthermore, in conventional fuel injection engines, fuel is injected simultaneously from a plurality of fuel injection valves, and in engines where fuel injection is performed during the intake stroke, the atomization time is short, resulting in poor combustion.

An object of the present invention is to provide a fuel supply device for a fuel injection engine that can improve fuel atomization and evaporation.

To achieve this object, according to the fuel supply device for a fuel injection engine of the present invention, an air injection boat that injects air so as to collide with the fuel injected from the fuel injection valve is provided near the fuel injection valve. , heating means is provided on the intake wall portion that is hit by the fuel injected from the fuel injection valves, which heats the engine when the engine temperature is below a predetermined temperature, and fuel injection from each fuel injection valve occurs when the intake valve is closing. Period and immediately after closing.

The present invention will be described in detail with reference to the drawings.

The intake system is provided with an air cleaner 1, an air flow meter 2, an intake pipe 3, a throttle body 4, a surge tank 5, and an intake pipe 6 in order from upstream. The intake pipe 6 is connected to the intake port 9 of the engine body 8.The fuel injection valve I3 is attached to the intake pipe 6 toward the intake port 9, and is connected to the fuel pipe 14. Ru.

An air injection boat 15 is provided near the fuel injection valve 13, and the air injection boat 15 is connected to the intake pipe 3 through a passage 16.
connected to. An air pump 17 is provided in the passage 16 and is driven by a crankshaft or an electric motor to pump air toward the air injection ports 15. Fuel injection valve 13
A heater (
A heater) 18 is provided. The combustion chamber 21 is defined by a cylinder head 22, a cylinder block 23, and a piston 24, and is supplied with fuel and air via an intake valve 25. The disks 29 and 30, which are provided with recesses or protrusions on their outer peripheries, are fixed to the shaft of the power distributor which is fixed to the crankshaft, and the rotation of the disks 29 and 30 is detected by electromagnetic pickups 31 and 32, respectively. Ru. The electromagnetic pickup 31 detects the reference position 1 of the crankshaft, and the electromagnetic pickup 32 detects the passage of a predetermined crank angle (for example, 30 degrees). The cylinder discrimination sensor 33 of the power distributor discriminates the cylinder in the explosion stroke based on the ignition signal. Detection signals from the electromagnetic pickups 31 and 32 and the cylinder discrimination sensor 33 are used to calculate the fuel injection timing. The water temperature sensor 34 is attached to the cylinder block 23 and detects the cooling water temperature, that is, the engine temperature. The electronic control device 37 receives input signals from the electromagnetic pickups 31 and 32, the cylinder discrimination sensor 33, and the water temperature sensor 34, and sends output signals to the fuel injection valve 13 and the switch 38. Switch enclosure is heater 18
The connection between the storage battery 39 and the storage battery 39 is controlled.

2 and 3 show the vicinity of the intake port 9. FIG. The heater is disposed on the lower half of the wall of the intake port 9, that is, on the side facing the fuel injection valve 13. The heater 18 may be arranged all around the inner wall of the intake port 9. A thermostat 40 made of bimetal is connected to the heater 18.
is maintained at a predetermined temperature.

FIG. 4 shows the fuel injection timing. In Figure 4, "suction" is the suction stroke, "pressure" is the compression process, "explosion" is the explosion stroke, and "
"Exhaust" means the exhaust stroke, and TDC means the top dead center of the first cylinder.Fuel injection is performed for each fuel injection valve 13 and corresponds to the beginning of the compression stroke.This is the period when the intake valve 25 is closing. Or, it corresponds to immediately after closing. Therefore, maximum time is secured until the injected fuel is sucked into the combustion chamber 21 and ignited, resulting in good fuel atomization. Also, when fuel is injected, the combustion chamber 21 2), the injected fuel hits the heater 18 correctly without being deflected.

The injected fuel from the fuel injection valve 13 collides with the injected air from the air injection port 15, thereby promoting atomization of the fuel.

When the engine is cold, that is, when the cooling water temperature is below a predetermined value (for example, the cooling water temperature is 40° C.), the switch is closed and current is supplied to the heater 18, and the heater 18 is in the operating state. Become. Thermostat 40 controls the current to heater 18 and the temperature of heater 18 to prevent abnormal temperature rise.

When the engine is at high temperature, the intake port 9 is maintained at a sufficiently high temperature due to the high-temperature cooling water, so that the evaporation of the adhering fuel is maintained satisfactorily without the heating effect of the heater 18.

As described above, according to the present invention, the injected fuel collides with the injected air from the air injection boat, and when the fuel is cold, the fuel adhering to the intake wall is heated by the heating means, and the fuel is injected into the intake air for each fuel injection valve. This occurs during the period when the valve is closing and immediately after closing. As a result, fuel atomization and evaporation are promoted, fuel consumption efficiency is improved, and harmful unburned components in the exhaust gas are reduced.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of an embodiment of the present invention, Fig. 2 is an enlarged view of the vicinity of the intake boat in Fig. 1, Fig. 3 is a view taken from direction ■ in Fig. 2, and Fig. 4 is a fuel injection timing. FIG. 9... Intake port, 13... Fuel injection valve, 15...
・Air injection port, 18... Heater, 31, 32...
...Electromagnetic pickup, 33...Cylinder discrimination sensor, 3
4...Water temperature sensor Figure 1 6

Claims (1)

[Claims] An air injection port that injects air so that it collides with the fuel injected from the fuel injection valve is provided near the fuel injection valve, and the part of the intake wall that is hit by the fuel injected from the fuel injection valve has an engine temperature below a predetermined temperature. A fuel supply for a fuel injection engine, characterized in that a heating means is provided which heats up when Device.